Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Toyo Kohan Co., Ltd.

Ikkoseiko Co., Ltd.

Katsuhiko Mori

Susumu Kitaoka

Shoji Yamashita

Kenjin Masumoto

Tomomichi Ueda

Masatoshi Hano

Tadahiro Tokumoto

Yoshihiro Kashihara

Tatsuo Tomomori

Yasushi Hirakawa

Kunio Tsuruta

Yoshinori Iwaizono

Seiichi Mizutani

Akira Iwase

Masao Suda

Hitoshi Omura

Hideo Omura

Kazuo Saito

Kazuhiko Watanabe

Tomiya Ishimaru

Yoshio Gohda

Tokiya Fujimoto

Hisashi Komeno

Kouhei Kitagawa

Shigekazu Tanaka

Kazuyuki Higashi

Toru Morimoto

Yoshinori Matsushita El Ind Co Ltd Iwaizono

A battery case is formed by drawing a metallic plate thin to form a cylindrical bodyhaving a closed end and cutting away part of the cylindrical bodyat an openingthereof in the direction perpendicular to an axis of the cylindrical body. The cutting of the cylindrical bodyis carried out by moving a second bladearranged outside the cylindrical bodyrelatively toward the axis of the cylindrical body with a first blade kept abutting the inner circumference of the cylindrical body. As a result, an inward burrextending in the direction perpendicular to the side face of the cylindrical bodyis formed on a cut surfaceof the cylindrical body, but the burris prevented from entering the battery case.

Method for manufacturing battery case and method for manufacturing hermetic battery

A battery can of the present invention ensures a stable and favorable contact with an electrode and thus makes it possible to obtain a highly reliable battery excellent in high rate discharge characteristics. The battery can having an opening, including a cylindrical side portion and a bottom portion, of the present invention is formed from a steel plate. The steel plate has an Ni&#x2014;Fe alloy layer on the inner face side of the battery can. The Ni&#x2014;Fe alloy layer has an oxide layer containing iron and having a thickness of 10 to 50 nm on the inner face side of the battery can.

Battery can and method for manufacturing the same

The method for producing a battery can according to this invention includes the steps of: (1) producing a battery can having a cylindrical side wall, a bottom, and an opening from a steel plate by a can-making process; (2) washing the battery can with tap water or industrial water; (3) washing the battery can with water having a conductivity of 80 &#x3bc;S/cm or less after the step (2); and (4) drying the battery can after the step (3).

Battery can, method for producing the same, and battery

A prismatic battery case with high dimensional precision is manufactured, while pursuing an improvement in productivity, with a manufacturing method of a prismatic battery case that includes a first step for molding an intermediate cup body () by impact molding a pellet () of prescribed shape, and a second step for molding a prismatic battery case () with a cross section of substantially rectangular shape by DI processing the intermediate cup body (). The DI processing conducts drawing and ironing continuously, in one action.

Square battery container, method of manufacturing the container, and square battery using the container

A prismatic battery case () has a configuration wherein a rectangular shorter-side plate () has a thickness (A) larger than a thickness (B) of a longer-side plate (). When the prismatic battery case () is manufactured, a battery case material () punched into a predetermined shape undergoes deep drawing to form a first intermediate cup element () having a substantially elliptic cross section; the first intermediate cup element () undergoes redrawing successively in a plural stages to form a second intermediate cup element () having a substantially elliptic cross section which is smaller in minor-axis-diameter to major-axis-diameter ratio; and the second intermediate cup element () undergoes DI processing to form the prismatic battery case () having a substantially rectangular cross section wherein the thickness (A) of the shorter-side plate () is made larger than the thickness (B) of the longer-side plate ().

Square cell container and method of manufacturing the cell container

A battery case ( ) is formed such that a thickness (t ) of a side wall ( ) with respect to a thickness (t ) of a bottom wall ( ) satisfies t &equals;&agr;t (&agr;&equals;0.2 to 0.7) undergoing an ironing step using ironing dies ( , and ) aligned in multiple stages, and that an inside face of the side wall is made to have a rough surface having average surface roughness of 0.2 &mgr;m to 2.0 &mgr;m by undergoing a drawing step after the ironing step. A manufacturing method of the battery case includes a first step of manufacturing a battery case element ( ) by applying the DI processing to a cup-shaped intermediate product ( ), and a second step of manufacturing a battery case by reducing an outside diameter to a predetermined outside diameter (r) without changing a thickness of a side wall by applying drawing processing to the battery case element by drawing dies ( and ) aligned in multiple stages.

Cell tube and method of manufacturing the cell tube

A protective circuit having an electronic circuit constructed on a circuit board is built into a sealing member that seals the open end of a battery case accommodating electricity generating elements. The circuit board is attached to the outer end of the sealing member. A positive terminal plate that becomes the positive terminal of the secondary battery and an S pole terminal plate that controls the operation of the electronic circuit by an external connection are provided on the outer surface of the circuit board. Thereby, a protective circuit that prevents over-discharging and overcharging is arranged inside the sealing member. A secondary battery is thereby constructed with a protective circuit without resorting to a construction of a battery pack.

Secondary battery

An explosion-proof non-aqueous electrolyte battery is provided which has a current cutoff device for cutting off electrical connection within the battery with safety and certainty in the event of overcharge while remaining inoperable in normal use or in storage at an elevated temperature. A pair of an upper vent plate,and a lower vent plate,mechanically and electrically coupled with each other is provided on the sealing part of-the battery where the mechanical coupling of the pair of the upper vent plate,and the lower vent plate,is so configured as to rupture and cut off an electric current in the event the internal pressure of the battery case increases beyond a predetermined value, and the rupture pressure at which the mechanical coupling between the pair of upper vent plate,and the lower vent plate,is broken has been set to decrease as the spatial volume occupancy ratio of the battery increases.

Explosion-proof nonaqueous electrolyte secondary cell and rupture pressure setting method therefor

The present invention relates to an explosion-proof seal plate for a sealed cell and a production method thereof and aims at providing an explosion-proof seal plate and production method thereof, wherein problems of a risk of explosion of a cell due to an excessive pressure inside the cell caused by abnormal generation of a gas through a chemical reaction accompanying over charge or erroneous use of the cell or damaging of electronic equipment using the cell as the power source are solved, ignition and other accidents can be prevented with a high accuracy by reliably cutting off an electric current when the cell internal pressure increases, and the increase in the resistance due to permeation of an electrolyte can be limited. In order to accomplish this aim, the present invention provides a thin portion,having a breaking strength of 18-24 kg/cm,in the central portion of an upper metallic foil,made of aluminum and a thin portion,having a breaking strength of 10-13 kg/cm,in the central portion of a lower metallic foil,made of aluminum, wherein the diameter A of the thin portion,of the upper metallic foil and the diameter B of the thin portion,of the lower metallic foil,satisfy the relation AB. The two metallic foils are welded at the central portions with an insulating gasket interposed, and encased in a metallic case,made of aluminum having 4 vent holes, on top of which a temperature dependent resistor,and a metallic cap,having 4 vent holes are then placed. A seal plate is obtained by sealing the periphery of the metallic case,, with which it is possible to prevent accidents such as ignition and explosion of a cell by reliably allowing internal gas to exhaust in the event of generation of a large volume of gas under an abnormal condition of a sealed cell.

Explosion-proof seal plate for enclosed type cell and production method thereof

This invention relates to a method to manufacture cell-cans by DI can method, by manufacturing a bottomed cylindrical cup-shaped intermediate product from a sheet material of which both surfaces are nickel plated and annealed in an atmosphere of inert gas making the metal nickel layer thickness and the hardness at predetermined values, then ironing the intermediate product at a predetermined ironing rate, securing a thickness of the metal nickel layer of more than 1.0 .mu.m and a Vickers hardness of more than HV 200 on the side wall of finished cell-cans. By this, conventional defect problems due to the cracks generated on the intermediate product can be solved completely and the problem of hair-lines formed on the surface of finished cell-can can be eliminated.

Method to manufacture cell-cans

Growing community of inventors

Osaka, Japan

Katsuhiko Mori